Generally, electronic devices incorporate various kinds of electronic parts inside a box-shaped cabinet to realize features corresponding to the electronic devices. Some of these electronic devices incorporate electronic parts that generates heat inside the cabinet, thereby adopt a structure in which a cooling fan is provided to cool down the electronic parts and prevent the temperature inside the cabinet from becoming high with the heat generated from the electronic parts and further an exhaust hole is provided in the cabinet so that the air heated by depriving the heat from the heat-producing electronic parts can be discharged from the exhaust hole.
For example, a notebook type personal computer (hereinafter, abbreviated as note PC) is internally equipped with a CPU, other heat-producing electronic parts, and many various kinds of electronic parts, and has a main unit equipped with a keyboard on the top face and a display unit equipped with a display screen hinge-mounted to the main unit to open and close freely. And the main unit incorporates a fan to cool down the CPU and the other heat-producing electronic parts, and is configured to discharge air from the exhaust hole provided in the sides of the cabinet or the like of the main unit.
The recent trend of ever more advanced functions and miniaturization of the note PC poses a problem about the position of the exhaust hole in the cabinet of the main unit. Generally, the left and right sides of the main unit cabinet is quite packed with various kinds of parts provided thereat, for example, such as a CD/DVD mounting port, a memory card loading port, various types of connectors, and an audio jack. Also, since the sides at the back of the main unit cabinet are similarly packed and a battery for driving the note PC is often placed at the back of the main unit, and in that case, the placement of a connector or the like in the sides of the back of the cabinet can be considerably limited. Since there is an operator at the front side of the main unit cabinet, it is impossible to discharge the heated air from the sides of the front side.
Under such circumstances, the number of parts disposed in the sides of the cabinet tends to increase with ever more advanced features, which makes it very difficult to secure a space for forming an exhaust hole of sufficient width, since area of the sides is becoming smaller with the advancement of miniaturization and slimness. This trend is common not only in the note PCs, but also in various types of electronic devices. See, for example, Japanese Laid-open Patent Publication Nos. 10-270879, 2000-227824, and 2001-345588.